So it seems that they've either been acquired by Myson or simply went broke. Nonetheless a lot of cheap devices based on the EC168 are still sold.

The only trace of E3C Tech is the Google cache:

Established in 2004, Tai-Hui provides total solutions to digital TV for the PC and portable device market. Our vision is to create technology for the 21st century that brings together the three dimensions of Consumer, Computer, and Communication.

Tai-Hui's current offering are EC168, EC188 and EC100. EC168 is a USB controller with a DVB-T demodulator while EC188 is a PCI controller with a DVB-T demodulator.